Investigating the effect of solar ambient and data characteristics on Ca II K observations and line profile measurements
arXiv:2303.17160 · doi:10.3847/1538-4357/acc529
Abstract
We analysed state-of-the-art observations of the solar atmosphere to investigate the dependence of the \ca brightness of several solar features on spectral bandwidth and spatial resolution of the data. Specifically, we study data obtained at the Swedish Solar Telescope with the CRiSP and CHROMIS instruments. The analyzed data, which are characterized by spectral bandwidth of 0.12 Å\ and spatial resolution of 0.078\arcsec, were acquired close to disc center by targeting a quiet Sun area and an active region. We convolved the original observations with Gaussian kernels to degrade their spectral bandwidth and spatial resolution to the instrumental characteristics of the most prominent series of \ca observations available to date. We then studied the effect of data degradation on the observed regions and on parameters derived from \ca line measurements that are largely employed as diagnostics of the solar and stellar chromospheres. We find that the effect of degrading the spectral resolution of \ca observations and line profiles depends on both the employed bandwidth and observed solar region. Besides, we found that the spatial degradation impacts the data characterized by a broad bandwidth to a larger extent compared to those acquired with a narrow band. However, the appearance of the observed solar regions is only slightly affected by the spatial resolution of data with bandwidths up to 1 Å\ and in the range [3,10] Å. Finally, we derived relationships that can be used to intercalibrate results from observations taken with different instruments in diverse regions of the solar atmosphere.
arXiv comment26 pages, 17 figures, ApJ accepted
References in corpus (30)
- The Solar Optical Telescope for the Hinode Mission: An Overview
- Kepler Mission Design, Realized Photometric Performance, and Early Science
- The CoRoT satellite in flight : description and performance
- CRISP Spectropolarimetric Imaging of Penumbral Fine Structure
- Sunrise: instrument, mission, data and first results
- The Imaging Magnetograph eXperiment (IMaX) for the Sunrise balloon-borne solar observatory
- The Sunrise Mission
- CRISPRED: A data pipeline for the CRISP imaging spectropolarimeter
- The second flight of the SUNRISE balloon-borne solar observatory: overview of instrument updates, the flight, the data and first results
- Multi-frame blind deconvolution with linear equality constraints
- SSTRED: Data- and metadata-processing pipeline for CHROMIS and CRISP
- Three-dimensional modeling of the Ca II H&K lines in the solar atmosphere
- Analysis of full disc Ca II K spectroheliograms. II. Towards an accurate assessment of long-term variations in plage areas
- Analysis of full disc Ca II K spectroheliograms III. Plage area composite series covering 1892-2019
- Full-disc Ca II K observations -- a window to past solar magnetism
- Temporal evolution and correlations of optical activity indicators measured in Sun-as-a-star observations
- Is the sky the limit? Performance of the revamped Swedish 1-m Solar Telescope and its blue- and red-beam re-imaging systems
- Analysis of full disc Ca II K spectroheliograms. I. Photometric calibration and CLV compensation
- Recovering the unsigned photospheric magnetic field from Ca II K observations
- Brightness of Solar Magnetic Elements as a Function of Magnetic Flux at High Spatial Resolution
- Observationally based models of penumbral microjets
- Reconstructing solar irradiance from historical Ca II K observations. I. Method and its validation
- Scrutinizing the relationship between plage areas and sunspot areas and numbers
- Delving into the Historical Ca II K Archive from the Kodaikanal Observatory: the Potential of the Most Recent Digitised Series
- Kanzelhöhe Observatory: instruments, data processing and data products
- Modeling stellar Ca II H & K emission variations. I. Effect of inclination on the S-index
- Characterization of chromospheric activity based on Sun-as-a-star spectral and disk-resolved activity indices
- Solar Cycle Variability and Surface Differential Rotation from Ca II K-Line Time Series Data
- From CoRoT 102899501 to the Sun. A time evolution model of chromospheric activity on the main sequence
- Penumbral decay observed in active region NOAA 12585